The telecommunications regulator has ordered small fixed-line carrier Wharf T&T to detail its network access within two weeks or face a fine.
The Office of the Telecommunications Authority made the order after Wharf T&T refused to provide it with a list of buildings connected to its network.
Ofta said Wharf T&T had cited the need to protect commercial secrets as the justification for its refusal. It did not accept Wharf T&T's argument.
Three other small carriers - Hutchison Global Communications, New World Telecommunications and Hong Kong Broadband Network - submitted network details to Ofta.
The regulator needs to identify which buildings have at least two self-built networks, including that of dominant carrier PCCW, in order to start a gradual roll-back of the mandatory Type II interconnection policy.
Under a policy announced by Ofta in July, any buildings that had at least two self-built networks could gradually phase out the mandatory Type II policy in three years, meaning PCCW would no longer be obligated to lease its last-mile capacity to rivals.
The regulator warned Wharf T&T that under its fixed-line licence agreement, it was obligated to report its network rollout details. Wharf T&T could face a financial penalty of between $200,000 and $10 million if it repeatedly ignored Ofta's directions.
Wharf T&T did not return calls yesterday.
Ofta said the networks built by HGC, NWT and HKBN had covered 60 per cent of Hong Kong's buildings, higher than the 50 per cent coverage it had estimated.